The invention relates generally to documentation of the construction of assemblies and systems and more particularly to the use of relational database software for the automated production of documentation for the construction and support of variably configured electrical or electronic assemblies and systems, including electronic assemblies and systems.
Documentation of the construction of electrical or electronic assemblies and systems is commonly accomplished with schematics, assembly drawings, parts lists and configuration logs. Schematics and assembly drawings are generated by drafting a design using either traditional manual drafting tools such as paper, pencil, triangles, squares, etc. or by modern computer aided design (CAD) software tools. Both of these methods result in drawings (illustrations and text) identifying the proper construction of electrical, electronic and mechanical subassemblies and assemblies. Parts lists or Bill of Materials are generally tabular information containing information such as the part number, description of the part, quantity of part used, unit of measure, source of supply and reference designated location of use. A configuration log is a parts list for a specific assembly potentially including identification information of the subassemblies contained within the assembly.
The purpose of a schematic is to illustrate the physical interconnection of components. The accuracy of a schematic may depend upon its use. An electrical schematic used to fabricate a printed circuit board needs to be very accurate for the circuit board to perform its intended function. On the other hand, a schematic for the wiring of a house may not need to be completely accurate for the wiring in the house to operate correctly because the electrician wiring the house can correct errors during installation.
The purpose of assembly drawings is to illustrate the mechanical assembly process and desired end result for the combination of several components. The accuracy of an assembly drawing also may depend upon its use. The architectural plans for a house may be very detailed when necessary to achieve a specific observable result, but may also be vague when details are left to the discretion of a skilled craftsman. For a high volume product produced by a factory, the drawings may need to be very accurate due to a company policy for documentation control or they may be allowed to be inaccurate when the factory has implemented other processes to correct the deficiencies. An assembly drawing will often contain instructions in addition to illustrations for clarity.
The purpose of the parts list is to identify the components required to produce an assembly. The parts list is often complemented with the schematic and/or assembly drawings to aid the assembler in achieving the desired result or end item. The parts list is typically correlated to the schematic by a reference designator which is an alpha-numeric string unique to the location of each part. The parts list is also typically correlated to the assembly drawing by either the reference designator or an item number which also uniquely identifies the location of each part.
The purpose of a configuration log is to record data such as serial numbers and parts numbers for subassemblies that make up an assembly. Manufacturers use configuration logs to record products shipped and shipping dates usually to identify the product""s warranty period or collect data about customers buying habits.
The industry standard for defining reference designated location of use is ANSI Y32.16-1975. This specification provides a method for defining and utilizing uniquely identified locations for components, subassemblies, assemblies and cables, as well as standards for marking such items to aid in construction.
Documentation produced by these traditional means is often error prone due to the inability of disparate systems to fully inter-operate. Factories responsible for the construction of assemblies often require several cycles of correction to the documentation in order to improve its clarity, consistency and correctness.
These traditional systems may also be time-consuming and therefore costly. They are usually very general purpose and therefore require very detailed and careful input and checking, especially for consistency between systems. Since the quality of the documentation is entirely determined by the care of the drafter and checker, inconsistent, missing, and misleading or ambiguous results are common.
Traditional systems work well for documenting assemblies with limited configuration options. Conversely, these systems are not as efficient for documenting the assembly instructions for highly re-configurable or variable systems.
An accurate database of configuration information may benefit a customer when a repair for an assembly is required. The information contained in the database may be essential to the repair and not readily available from other sources. For example, a repair manual for a highly re-configurable assembly may simply not be able to identify all configuration options and corresponding repair procedures.
The present invention complements the traditional methods of documenting re-configurable assemblies by simplifying the creation of the variable portion of the documentation for assemblies with significant configuration options.
Tabular and other data representing the construction of assemblies and systems is entered in a relational database. The relational database produces output consisting of reports representing the construction of the assembly. The relational database is preferably structured to use an applicable industry standard such as ANSI Y32.16-1975 specifications with modifications necessary to allow for the coherent representation of data within a relational database.
The relational database contains two categories of information. The first category consists of lookup tables containing commonly or repetitively used data. The second category is assembly specific tables containing links or relationships to the lookup tables for commonly used data and additional data unique to the particular assembly.
The lookup tables contain two types of data. The first type defines the generic or unpopulated assembly by its list of reference designated locations. For example, for electrical and electronic assemblies, the list of locations may exclude cables since cables interconnect subassemblies at different locations. However, cables are identified by unique reference designators. The second type defines the list of all components and subassemblies (parts) and their characteristics. The characteristics of components and subassemblies may include configuration parameters and interfaces. Configuration parameters are significant elements of data about a component or subassembly. Interfaces are places on the component or subassembly where electrical or mechanical connections from other components or subassemblies are possible. The definition of the reference designated locations may restrict the parts eligible for use in any particular location. The definition of the interfaces may restrict the eligibility of mating interfaces for later assembly. Additionally, parts may be categorized into part types. Some part types may have common properties that differ from other part types. For example, cables may be excluded from location definitions or software may be excluded from supporting the definition of interfaces.
The assembly specific data tables combine the definition of reference designated locations with a list of parts specific to an assembly. The characteristics of the specific parts used in the assembly are available from the relationship to the parts definition contained in the parts list lookup tables. The assembly specific data includes relationships defining the reference designated locations, the specific parts list and additional unique part characteristic data such as configuration parameter values and interconnection data. The values of configuration parameters provide data unique to the use of a part within a specific assembly. The interconnection data provides a cross reference of electrical and mechanical connections within a specific assembly. A specific assembly may either be a specific configuration of an assembly produced in some quantity or a unique assembly, perhaps identified by a serial number. The fundamental process for defining an assembly consists first of creating a list of parts. The parts are then assigned to the pre-defined locations within the final assembly. Then the parts are interconnected within the assembly and finally, configuration parameter values are assigned. A report may be generated to present this information in an orderly, understandable way. Other data managed by the database may require additional steps in the fundamental process.
The benefit of having a definition of the reference designated locations in the assembly is that parts may be selected from the parts list and assigned to appropriate locations (where they belong). The benefit of having a definition of the characteristics of a part is that the important characteristics of a part are known and recorded consistently. The benefit of having a definition of the interfaces of a part is that the definition of one interface may be used to select an appropriate mating interface. The existence of these definitions, which only occurs once for each assembly and part, enables the rapid construction of many different configurations of the parts within the assembly. The use of a relational database to perform this process enables the addition of significant error prevention and error detection capabilities to the process, thus enhancing the accuracy of the data contained within the assembly definition. The database also allows reporting of almost any conceivable data analysis.
A single database may contain any number of reference designated location definitions, part definitions and assembly definitions. A good database design would incorporate user friendly forms for user data input and various reports that may be printed for reference. The preferred embodiment will present the underlying schema or database table structure for the present invention. The process for using the database will be shown. The user interface, query and report designs are not presented in this document as their implementation will be readily apparent to one skilled in the art. A sample report from the database is presented to support the preferred embodiment.
The preferred embodiment presents a relational database system for defining the construction of variably configured computer systems. These computer systems consists of cabinets populated with modular components such as power supplies, circuit card assemblies, mass memory devices, loaded software, and human machine interface (HMI) devices such as keyboards, trackballs and monitors. The invention, however, is not limited to the construction, repair or maintenance of such computer systems. It may be used for virtually any item of manufacture, particularly with products have a variety of different configurations, such as automobiles and many other types of goods. The described embodiment may also be used to document the configuration of a system of computers on a local area network in a building. In its most general sense, the present invention documents a system of interconnected nodes at specified physical locations, the nodes having various properties or configuration parameters that define their function. In the claims of this document, the word xe2x80x9cunitxe2x80x9d includes items of manufacture as well as interconnected node systems, or for the wiring of buildings, ships, planes, telephone switching centers and many other applications.